The DIN 558 standard specifies the dimensions and technical requirements for hexagon head bolts with a thread length of one diameter in steel or stainless steel materials. These bolts are designed for general engineering use and are available in different sizes to accommodate various applications. The standard outlines the properties of the bolts, including their mechanical and chemical composition, as well as their tolerance and dimensions. DIN 558 also provides guidance on the markings that should be present on the bolts for easy identification and traceability. Overall, this standard ensures that hexagon head bolts manufactured in accordance with DIN 558 meet the necessary quality and performance criteria for use in engineering and construction projects.